You can create your own theme. The easiest approach is to pick one of the existing themes that is closest to what you require, say Metro, then go to .\Tools\SDI\Themes and copy the theme *.txt file and folder to a new name. Don’t modify an existing theme directly because it will be overwritten on the next update. Edit the the theme *.txt file using your favourite text editor. For example, to change the font color of the driver items to black, look for DRVITEM_TEXT1_COLOR and change the value to 0x000000.
DRVITEM_TEXT1_COLOR = 0x000000
I won’t say it’s easy, there’s no reference but you’ll work it out eventually. Not all themes contain every available value.